A loudspeaker module is an important acoustic component in a portable electronic terminal and used to perform conversion between an electrical signal and a sound signal, and serves as an energy conversion device. The current loudspeaker module usually comprises a casing in which a speaker unit is received, and the speaker unit comprises a vibration system and a magnetic circuit system. An inner cavity of the current loudspeaker module is divided by the vibration system into two cavities: one is a front acoustic cavity located in front of the vibration system, the front acoustic cavity being communicated with a front sound exit hole of the loudspeaker module and being used to propagate out sound emitted by the speaker unit; the other one is a rear acoustic cavity behind the vibration system. The rear acoustic cavity is a closed cavity and used to boost low-frequency performance of the loudspeaker module and prevent acoustic short-circuiting. To achieve the acoustic performance of the loudspeaker module, the rear acoustic cavity usually needs to have a certain volume, which causes a larger volume of the loudspeaker module. However, the current portable electronic terminal develops in a light-weighted, thinner and compact direction, for example, a Pad (a tablet personal computer) becomes smaller and thinner. In this case, a larger loudspeaker module cannot be installed in the electronic terminal, and cannot meet needs of the electronic terminals which are getting increasingly lighter and thinner.